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<TITLE>[Chapter 18] 18.39 java.awt.MediaTracker (JDK 1.0)</TITLE>
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<h2 CLASS=sect1><A CLASS="TITLE" NAME="JNUT2-CH-18-SECT-39">18.39 java.awt.MediaTracker (JDK 1.0)</A></h2>

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<P CLASS=para>
This class provides a very convenient way to asynchronously
load and keep track of the status of any number of
<tt CLASS=literal>Image</tt> objects.  You can use it to load one or more
images and to wait until those images have been completely
loaded and are ready to be used.  

<P CLASS=para>
The <tt CLASS=literal>addImage()</tt> method registers an image to be
loaded and tracked and assigns it a specified identifier
value.  <tt CLASS=literal>waitForID()</tt> loads all images that have been
assigned the specified identifier and returns when they have
all finished loading or it has received an error.
<tt CLASS=literal>isErrorAny()</tt> and <tt CLASS=literal>isErrorID()</tt> check whether
any errors have occurred while loading images.
<tt CLASS=literal>statusAll()</tt> and <tt CLASS=literal>statusID()</tt> return the status
of all images or of all images with the specified
identifier.  The return value of these two methods is one of
the defined constants.

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public class <tt CLASS=literal>MediaTracker</tt> extends Object implements Serializable {
    // <tt CLASS=literal>Public Constructor</tt>
            public <tt CLASS=literal>MediaTracker</tt>(Component <tt CLASS=literal>comp</tt>);
    // <tt CLASS=literal>Constants</tt>
            public static final int <tt CLASS=literal>ABORTED</tt>;
            public static final int <tt CLASS=literal>COMPLETE</tt>;
            public static final int <tt CLASS=literal>ERRORED</tt>;
            public static final int <tt CLASS=literal>LOADING</tt>;
    // <tt CLASS=literal>Public Instance Methods</tt>
            public void <tt CLASS=literal>addImage</tt>(Image <tt CLASS=literal>image</tt>, int <tt CLASS=literal>id</tt>);
            public synchronized void <tt CLASS=literal>addImage</tt>(Image <tt CLASS=literal>image</tt>, int <tt CLASS=literal>id</tt>, int <tt CLASS=literal>w</tt>, int <tt CLASS=literal>h</tt>);
            public boolean <tt CLASS=literal>checkAll</tt>();
            public boolean <tt CLASS=literal>checkAll</tt>(boolean <tt CLASS=literal>load</tt>);
            public boolean <tt CLASS=literal>checkID</tt>(int <tt CLASS=literal>id</tt>);
            public boolean <tt CLASS=literal>checkID</tt>(int <tt CLASS=literal>id</tt>, boolean <tt CLASS=literal>load</tt>);
            public synchronized Object[] <tt CLASS=literal>getErrorsAny</tt>();
            public synchronized Object[] <tt CLASS=literal>getErrorsID</tt>(int <tt CLASS=literal>id</tt>);
            public synchronized boolean <tt CLASS=literal>isErrorAny</tt>();
            public synchronized boolean <tt CLASS=literal>isErrorID</tt>(int <tt CLASS=literal>id</tt>);
        <b>1.1</b>  public synchronized void <tt CLASS=literal>removeImage</tt>(Image <tt CLASS=literal>image</tt>);
        <b>1.1</b>  public synchronized void <tt CLASS=literal>removeImage</tt>(Image <tt CLASS=literal>image</tt>, int <tt CLASS=literal>id</tt>);
        <b>1.1</b>  public synchronized void <tt CLASS=literal>removeImage</tt>(Image <tt CLASS=literal>image</tt>, int <tt CLASS=literal>id</tt>, int <tt CLASS=literal>width</tt>, int <tt CLASS=literal>height</tt>);
            public int <tt CLASS=literal>statusAll</tt>(boolean <tt CLASS=literal>load</tt>);
            public int <tt CLASS=literal>statusID</tt>(int <tt CLASS=literal>id</tt>, boolean <tt CLASS=literal>load</tt>);
            public void <tt CLASS=literal>waitForAll</tt>() throws InterruptedException;
            public synchronized boolean <tt CLASS=literal>waitForAll</tt>(long <tt CLASS=literal>ms</tt>) throws InterruptedException;
            public void <tt CLASS=literal>waitForID</tt>(int <tt CLASS=literal>id</tt>) throws InterruptedException;
            public synchronized boolean <tt CLASS=literal>waitForID</tt>(int <tt CLASS=literal>id</tt>, long <tt CLASS=literal>ms</tt>) throws InterruptedException;
}
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